Video compression demuxes, decodes, and encodes in this tab with WebCodecs. A 2026-10-26 high-bitrate color-bars clip went from 2976898 bytes to 149460 bytes. That export is smaller. The live controls are destination chips for a Discord 19 MB encoding target, email 25 MB, WhatsApp 64 MB, and WhatsApp 100 MB, plus Fast, Balanced, and Smallest.
Video compression demuxes, decodes, and encodes in this tab with WebCodecs. A 2026-10-26 high-bitrate color-bars clip went from 2976898 bytes to 149460 bytes. That export is smaller.
The live controls are destination chips for a Discord 19 MB encoding target, email 25 MB, WhatsApp 64 MB, and WhatsApp 100 MB, plus Fast, Balanced, and Smallest. Advanced controls cover resolution, frame rate, codec, a quality slider, keeping audio, and an approximate megabyte target. A chip sets an upper target for this encoder. It does not mean Discord, a mail host, or WhatsApp will accept the file.
The file picker accepts MP4, MOV, WebM, and MKV when the browser can decode them. The 2026-10-26 color-bars export is 149460 bytes from a 2976898 byte input.
Container tags left out of the new file are not a full metadata-removal report. Image, PDF, and video-tag cases are on the metadata removal report.
This page has no frames-per-second ranking.
A size target is the upper size you set for this encoder.
2026-10-09 single-sample production test
Three rows from one 10-second clip, recorded on 2026-10-09.
Anonymous clip: 10 seconds, 720×1280, 24 fps, 240 frames, H.264, no audio track, 9,491,383 bytes. All three runs kept Original size and FPS, Auto codec, quality 50.
Preset
Size target
Output
Output bytes
Change
SSIM
Same-frame note
Balanced
Off
H.264
1439264
−84.84%
0.898303
Same-frame comparisons showed damage to hair, accessories, and fabric.
Balanced
On, 5 MB upper target
H.264
4071380
−57.10%
0.955849
Best detail of these three on this sample, still lossy. 5 MB is an upper target, not a precise output promise.
Smallest
Off
VP9 WebM
949127
−90.00%
0.881243
Detail loss.
SSIM in this table is the score recorded for this clip.
All three outputs decoded 240 frames and the full 10 seconds. Matching frames were compared. No full real-time viewing or listening acceptance was performed. The original had no audio.
Rounded timing from that run
The UI showed about 1 / 1 / 2 seconds. Those readings are rounded. This run did not record an exact Chrome version.
The table below on this page is the published compression record: a 2026-10-26 color-bars export, 2976898 bytes to 149460 bytes.
These are the recorded settings and byte counts for this clip.
Size outcome
Recorded value
Preset
smallest
Quality
20
Size target
Off
Original resolution
1280×720
Original frame rate
24
Output codec
vp9 + opus
Input bytes
2976898
Output bytes
149460
Byte change
-2827438
If you need a smaller file, try a lower resolution, a lower quality, or a size target as a suggestion, then compare the same frame and the exported bytes before you keep the result.
Generated CC0 lab input on 2026-10-26 with ffmpeg 6.1.1: testsrc2 1280x720, 24 fps, 2 seconds, sine 440 Hz, libx264 ultrafast CBR 12000k, AAC 128k. Original lab input, not a camera recording.
This download probed as vp9 with opus audio. Output is 149460 bytes and the input fixture is 2976898 bytes. The output file is smaller than the input on this clip. ffprobe duration was 2.02 seconds. Elapsed 455ms is for this environment only.
Output is 149460 bytes and the input fixture is 2976898 bytes. The output file is smaller than the input on this clip. Elapsed 455ms is for this environment only.
elapsedMs
455
elapsedScope
this environment only
Limitations recorded for this case
Captured on 2026-10-26 in headless Chrome/156.0.8078.47 against the local Video Compressor page at commit bf34759887a62ae15fdb13404a9f2fcf6aa568b9. This case is not part of the 2026-10-02 shutter.
ffprobe read the output duration as 2.02 seconds against a 2.00 second input. That reading is this file only.
Screenshots from the capture
Input · ready · 1088×913. Video compressor for cpk-lab-cc0-high-bitrate-bars-1280x720.mp4. Read-back preset smallest, target off, quality 20.Output · done · 1088×1805. Video compressor result for cpk-lab-cc0-high-bitrate-bars-1280x720.mp4. Output 149460 bytes, input 2976898 bytes.
